Cathodic protection and applications of selenium rectifiers

Cathodic protection has been in common usage on petroleum pipe lines since about 1910 and has also been applied successfully to a considerable variety of other structures. Se rectifiers offer numerous advantages for provision of the necessary l.v. current for such protection, since they may be enclosed in units which are light, compact, portable, suitable for pole mounting, and their operation is substantially uniform over the wide temperature fluctuations encountered in outdoor use. Their efficiency remains substantially constant through comparatively large load variations. An account is given of methods of utilizing Se rectifiers for cathodic protection of pipe lines, tank farms, refineries, steel pipes in towns used for water and l.p. gas distribution, aqueducts, submerged structures, etc.